Corsa diesel starter motor

It might be the starter on the way out, but first I would have a good check of all the battery and engine earth leads, undo and clean them. Your symptoms sound exactly like a poor connection, by keeping trying the current can fizzle away at the corrosion and get a good temporary connection and then it starts.

Try the cheap things 1st, check the earth bond beteween the engine & the body & the battery & the body's intact & tight, then check the starter cable. If they're good stick a multimeter on the battery & watch the voltage as it cranks.

Thanks for the replies,

Corrosion is a possibility as I have a split pipe leading to the heater matrix and I just top up with water as haven't had time to mend yet. Only been like that for 6 weeks now so you wouldn't expect corrosion as I'm only putting water in, however originally the leak would've contained antifreeze.

Thanks again and will check for corrosion.

Jon

one of the properties of anti-freeze is to prevent the corrosion that plain water causes. I suggest that even if you CBA to fix the leak that you keep it topped up with the proper anti-freeze mix or all sorts of nasty hard to fix leaks will start to develop elsewhere, not to mention invisible problems like the cylinder head rotting away internally.